TCP_NODELAYを1にするプログラム．できているのかは謎い．

get_and_set_tcp_nodelay.c

#include <stdio.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netinet/tcp.h>

int main() {
    int sock;
    int val, setval;
    struct sockaddr_in addr;
    char buf[2048];
    int len = sizeof(val);
    int result;

    setval = 1;

    sock = socket(AF_INET, SOCK_STREAM, 0);

    if(getsockopt(sock, IPPROTO_TCP, TCP_NODELAY, &val, &len) == -1 ){
        perror("failed to getsockopt");
    }

    printf("Current TCP_NODELAY: %d\n",val);
    val = 1;

    if(setsockopt(sock, IPPROTO_TCP, TCP_NODELAY, &val, len) == -1 ){
        perror("failed to setsockopt");
    }

    printf("Current TCP_NODELAY: %d\n",val);

    close(sock);

    return 0;
}

I referred to the following URL to write this code. Thanks a lot.
下記のURLを参考させていただきました，ありがとうございます．

http://kazmax.zpp.jp/cmd/t/tcp.7.html
http://kazmax.zpp.jp/cmd/g/getsockopt.2.html
http://nxmnpg.lemoda.net/ja/2/setsockopt
http://d.hatena.ne.jp/odawara/20071116/1195190287
http://d.hatena.ne.jp/iww/20100409/1270823223
https://stackoverflow.com/questions/1045530/how-to-set-tcp-nodelay-on-bsd-socket-on-solaris
http://d.hatena.ne.jp/sleepy_yoshi/20111113/p1